Recurrent anterior glenohumeral instability after attempted soft
tissue stabilization can be secondary to failed repair, capsular
redundancy, and more commonly from lack of bony support. The latter can
be secondary to glenoid bone loss and concomitant articular bony
deformities. (1) Isolated labral repair and capsular plication in
patients with critical glenoid bone defects are often insufficient in
preventing recurrent dislocation. Stabilization procedures to
reconstitute structural deficits have been shown to reliably restore
anterior stability. (2) The Latarjet procedure involves the transfer of
the coracoid process with its soft tissue attachments, (3) thereby
providing both bony and soft tissue articular reinforcement with a low
incidence of postoperative failure. (4-7) However, complications, such
as coracoid fracture, glenohumeral arthrosis, and screw migration, can
be detrimental to articular anatomy. (5) In a patient with recurrent
anterior instability after two attempts at soft tissue stabilization
(arthroscopic labral repair followed by open inferior capsular shift),
an open Latarjet procedure was performed with subsequent revision
secondary to coracoid autograft fracture.

Case

A 45-year-old man presented for evaluation of persistent left
shoulder anterior instability after two failed anterior reconstructive
procedures at an outside institution. He had undergone arthroscopic
superior labral anterior to posterior (SLAP) repair with anterior
capsulorrhaphy in 2013. Owing to persistent instability, an open
inferior capsular shift was performed in 2014. Following this second
procedure, he continued to have recurrent instability. Upon his
presentation to our institution, his examination demonstrated positive
anterior apprehension and a positive relocation test with 2+ anterior
instability. The patient had no evidence of generalized excessive joint
laxity with a negative sulcus sign and no signs of posterior
instability. Neurological exam of the extremity was otherwise normal.

Due to previous placement of a neurostimulator in the
patient's back, magnetic resonance imaging (MRI) could not be
performed. Left shoulder radiographs in anteroposterior (AP) internal
rotation, AP external rotation, trans-scapular-Y, West Point, and
axillary views suggested a small Hill-Sachs lesion without evidence of a
concomitant Bankart lesion (Fig. 1). A three-dimensional computed
tomography (CT) scan was obtained to further evaluate potential bony
defects and revealed a small Hill-Sachs lesion as well as cortical
irregularity along the anteroinferior glenoid rim without significant
bony deficiency (Fig. 2).

At the time of surgery, examination under anesthesia revealed gross
instability, primarily anteriorly with instability of 2+ to 3+ noted, as
well as 2+ sulcus, and 2+ posterior instability. The patient was placed
into the beach chair position and a Latarjet procedure was performed. A
modified deltopectoral incision was utilized. The subscapularis muscle
tendon was torn and retracted to the mid humeral level with a large
tendinous stump laterally. This was separated from the capsule and
tagged with #2 FiberWire[R] (Arthrex, Inc., Naples, FL). The pectoralis
minor was elevated from the medial aspect of the coracoid, and the
acromioclavicular (AC) ligament was incised at the level of the acromion
to allow for adequate stump length to incorporate into the capsular
repair. The coracoid drill holes were prepared using the Mitek Latarjet
system (DePuy Mitek, Inc., Raynham, MA). The coracoid guide was placed
followed by guidewires over which a cannulated reamer was utilized to
prepare the coracoid drill holes. A curved oscillating saw was then
utilized to cut the base of the coracoid, taking care not to damage the
coracoclavicular ligaments. A vertical capsular incision was performed
at the level of the glenohumeral joint followed by removal of the
capsule at this level and medial along the anterior neck of the scapula.
No major glenoid bone defects were noted. The coracoid graft was
transferred and placed flush against the articular surface on the
inferior glenoid from the 3:30 to 5 o'clock position. Two 36 mm
screws were used to secure the graft. After graft insertion, shoulder
stability was evaluated: the humeral head was maintained in position at
90[degrees] of abduction and 90[degrees] of external rotation. The
coracoacromial ligament on the lateral aspect of the coracoid was
incorporated into the capsular repair. The subscapularis muscle was then
repaired via bone tunnels and suture anchors to the lesser tuberosity.
Postoperatively, the patient was placed in an abduction brace in neutral
shoulder rotation.

The patient was brought back to the operating room for revision
surgery. Intraoperatively the fragments were identified with the distal
fragment still attached to the conjoint tendon. The conjoint tendon was
scarred into the anteroinferior capsule and functioning as an anterior
restraint. The proximal fragment was removed. No intra-articular damage
was found. The two screws securing the coracoid to the glenoid were
removed. The distal bony fragment was reattached to the anterior
inferior portion the glenoid with two 3.0 mm PEEK suture anchors
(Arthrex, Inc., Naples, FL), (Fig. 5). The sutures were passed through
the remaining coracoid bone block and conjoint tendon and tied.

Postoperatively, the patient was kept in an abduction brace with
the shoulder in neutral rotation for 6 weeks. Gentle passive pendulum
exercises were started immediately. At 6 weeks postoperatively, shoulder
abduction and external rotation were initiated. The patient was last
seen at 6-months follow-up and had minimal pain with overhead
activities. He did not report any instability and was satisfied with his
result.

Discussion

In the setting of recurrent anterior shoulder instability,
determining the extent of both bony and soft tissue defects is crucial
for optimal operative management. Arthroscopic Bankart repair is an
established option for patients with isolated soft tissue Bankart
lesions, yet Burkhart and coworkers reported a near 70% instability
recurrence rate following soft tissue stabilization with underlying bony
Bankart or Hill-Sachs lesions. (8) More extensive soft tissue injuries,
including capsular attenuation, also have a high association with
recurrent instability following Bankart repair. (9) The Latarjet
procedure, which was first described in 1954, (3) is becoming a popular
option for surgeons managing patients with recurrent instability with or
without significant bony defects. The known presence of significant
anterior glenoid bone loss (generally beyond 25%) (10) from either a
fracture or attritional bone loss can be successfully treated with
Latarjet reconstruction. (11) An engaging Hill-Sachs defect, often in
coexistence with a Bankart lesion, is also an indication for the
procedure. (8) One can also advocate that a Latarjet procedure be used
as the initial stabilization procedure in extremely active or athletic
patients who do not have significant bone loss.

Latarjet stabilization successfully addresses the problem of
recurrent instability in several ways. The most obvious benefit is from
restoration of the glenoid contact surface area. Coracoid relocation to
the anterior glenoid rim also increases the glenoid articular arc,
allowing for more external rotation of the shoulder without engagement
of a HillSachs lesion. The coracobrachialis functions as a static and
dynamic stabilizer to the inferior part of the capsule during shoulder
abduction and simultaneous elbow flexion. (12) This is otherwise known
as the dynamic sling effect.

Most studies show positive outcomes with the open Latarjet
procedure, with complications at rates as low as 1% (13) and
predominately secondary to technical error. Perioperative complications
may include musculocutaneous nerve palsy, hematoma formation, coracoid
fracture, and coracoid graft osteolysis. (13) Protecting the
coracobrachialis muscle during coracoid osteotomy and subsequent
transfer can help prevent transient or permanent musculocutaneous nerve
injury. (14) Coracoid fracture at the time of bony fixation can be
secondary to using large screws, excessive compressive forces from screw
overtightening, or eccentric screw placement in the coracoid as was seen
in this case. Osteolysis of the coracoid graft is most likely secondary
to insufficient vascularization or coracoid-glenoid contact and can lead
to re-engagement of a Hill-Sachs lesion. (12) Screw loosening can cause
symptomatic coracoid movement, while total screw displacement has been
noted to cause major intra-articular damage. (15) Postoperative coracoid
fracture, in addition to improper intraoperative technique, can be
caused by trauma.

Glenohumeral arthrosis is a well-established long-term complication
of Latarjet surgery, occurring with rates as high as 62%. The number one
predisposing factor is improper coracoid graft orientation. The coracoid
graft should ideally be fixed perpendicular to the scapular plane on the
anterior glenoid rim. Additionally, lateral placement of the graft in
the coronal plane can effectively create articular step-off and is
strongly associated with glenohumeral arthrosis.

The case presented specifically highlights the need to
appropriately identify the "bony margins" of the coracoid
prior to drilling to make certain that drill holes are not eccentrically
placed. The soft tissue attachments to the coracoid (lateral
coracoacromial ligament stump and medial pectoralis minor tendon) need
to be adequately elevated off the coracoid to visualize the bony margins
and appropriately center the drill guide.

Disclosure Statement

Laith M. Jazrawi, M.D., receives research support from Arthrex,
Inc. (Naples, FL) and DePuy Mitek (Raynham, MA). None of the other
authors have a financial or proprietary interest in the subject matter
or materials discussed, including, but not limited to, employment,
consultancies, stock ownership, honoraria, and paid expert testimony.